MCP Google Contacts Server

Instructions

    Args:
        resource_name: Contact resource name (people/*)
        given_name: Updated first name
        family_name: Updated last name
        email: Updated email address
        phone: Updated phone number
        organization: Updated company/organization name
        job_title: Updated job title or position
        address: Updated physical address
        birthday: Updated birthday in YYYY-MM-DD format
        website: Updated website URL
        notes: Updated notes or biography
        nickname: Updated nickname
    

Implementation Reference

• src/tools.py:230-298 (handler)

  The handler function for the 'update_contact' MCP tool. It collects optional field updates into a contact_data dict and delegates to the GoogleContactsService.update_contact method.

  @mcp.tool()
  async def update_contact(
      resource_name: str,
      given_name: Optional[str] = None,
      family_name: Optional[str] = None,
      email: Optional[str] = None,
      phone: Optional[str] = None,
      organization: Optional[str] = None,
      job_title: Optional[str] = None,
      address: Optional[str] = None,
      birthday: Optional[str] = None,
      website: Optional[str] = None,
      notes: Optional[str] = None,
      nickname: Optional[str] = None,
  ) -> str:
      """Update an existing contact with comprehensive field support.
  
      Args:
          resource_name: Contact resource name (people/*)
          given_name: Updated first name
          family_name: Updated last name
          email: Updated email address
          phone: Updated phone number
          organization: Updated company/organization name
          job_title: Updated job title or position
          address: Updated physical address
          birthday: Updated birthday in YYYY-MM-DD format
          website: Updated website URL
          notes: Updated notes or biography
          nickname: Updated nickname
      """
      service = init_service()
      if not service:
          return "Error: Google Contacts service is not available. Please check your credentials."
  
      try:
          contact_data = {}
  
          # Add fields that are being updated
          if given_name is not None:
              contact_data["given_name"] = given_name
          if family_name is not None:
              contact_data["family_name"] = family_name
          if email is not None:
              contact_data["email"] = email
          if phone is not None:
              contact_data["phone"] = phone
          if organization is not None:
              contact_data["organization"] = organization
          if job_title is not None:
              contact_data["job_title"] = job_title
          if address is not None:
              contact_data["address"] = address
          if birthday is not None:
              contact_data["birthday"] = birthday
          if website is not None:
              contact_data["website"] = website
          if notes is not None:
              contact_data["notes"] = notes
          if nickname is not None:
              contact_data["nickname"] = nickname
  
          if not contact_data:
              return "Error: No fields provided for update."
  
          contact = service.update_contact(resource_name, contact_data)
          return f"Contact updated successfully!\n\n{format_contact(contact)}"
      except Exception as e:
          return f"Error: Failed to update contact - {str(e)}"

• src/google_contacts_service.py:423-492 (helper)

  Core service helper method that handles the Google People API updateContact call, including building the request body from contact_data, determining update fields, and formatting the response.

  def update_contact(self, resource_name: str, contact_data: Dict[str, Any]) -> Dict[str, Any]:
      """Update an existing contact with comprehensive field support.
  
      Args:
          resource_name: Contact resource name
          contact_data: Dictionary containing updated contact information
  
      Returns:
          Updated contact dictionary
      """
      try:
          # Get current contact for etag
          current_person = (
              self.service.people()
              .get(resourceName=resource_name, personFields=",".join(self.PERSON_FIELDS))
              .execute()
          )
  
          etag = current_person.get("etag")
  
          # Build update body using the same logic as create
          update_body = self._build_contact_body(contact_data, current_person)
          update_body["etag"] = etag
          update_body["resourceName"] = resource_name
  
          # Map input fields to API fields for updatePersonFields
          field_mapping = {
              "given_name": "names",
              "family_name": "names",
              "nickname": "nicknames",
              "email": "emailAddresses",
              "emails": "emailAddresses",
              "phone": "phoneNumbers",
              "phones": "phoneNumbers",
              "address": "addresses",
              "addresses": "addresses",
              "organization": "organizations",
              "job_title": "organizations",
              "birthday": "birthdays",
              "website": "urls",
              "urls": "urls",
              "notes": "biographies",
              "relations": "relations",
              "events": "events",
              "custom_fields": "userDefined",
          }
  
          # Determine which API fields to update based on input
          update_fields = set()
          for input_field in contact_data.keys():
              if input_field in field_mapping:
                  update_fields.add(field_mapping[input_field])
  
          if not update_fields:
              return self._format_contact_enhanced(current_person)
  
          # Execute update
          updated_person = (
              self.service.people()
              .updateContact(
                  resourceName=resource_name,
                  updatePersonFields=",".join(update_fields),
                  body=update_body,
              )
              .execute()
          )
  
          return self._format_contact_enhanced(updated_person)
  
      except HttpError as error:

• src/main.py:74-75 (registration)

  Call to register_tools(mcp) in main.py, which triggers registration of all tools including update_contact via chained register_contact_tools(mcp).

  register_tools(mcp)

• src/tools.py:64-73 (registration)

  Top-level registration function that calls register_contact_tools(mcp), where the update_contact tool is defined and registered.

  def register_tools(mcp: FastMCP) -> None:
      """Register all Google Contacts tools with the MCP server.
  
      Args:
          mcp: FastMCP server instance
      """
      register_contact_tools(mcp)
      register_directory_tools(mcp)
      register_contact_group_tools(mcp)

• src/tools.py:75-76 (registration)

  Function that defines and registers the update_contact handler using nested @mcp.tool() decorator (excerpt shows beginning; full function spans to line 338).

  def register_contact_tools(mcp: FastMCP) -> None:
      """Register contact management tools with the MCP server."""